Implantable medical devices (IMDs) are now used to provide countless therapies and to monitor a wide variety of physiological events. With the increased uses of IMDs has also come the need for improved methods of communicating with and between IMDs.
Conventionally, communication with IMDs has been with magnetic field communication systems. Such systems, however, are generally only capable of communicating over very short distances, on the order of a few inches. As a result, a magnetic head of a programmer (or other external device) must be located on or near the IMD for communication to occur. More recently, radio frequency (RF) communication systems have been developed for use with IMDs. RF communication provides a number of benefits over magnetic field communication systems, including much greater communication distances.
Because an IMD is surgically implanted within the body of a patient, battery life is one of the considerations in the design of IMD communication systems. Methods of reducing the amount of time that the receiver of an IMD operates can be beneficial in improving.